Whenever I get an idea for a song, even before jotting down the notes, I can hear it in the orchestra, I can smell it in the scenery, I can see the kind of actor who will sing it, and I am aware of an audience listening to it.
It may be that that we can sing what we often cannot say, whether it be from shyness, fear, lack of the right words or the passion or dramatic gift to express them. More souls have rallied to more causes by the strains of music than by straining rhetoric.
If somebody wants to sing my songs after I'm gone, nobody will be happier than my dead body.